Police bought crack cocaine with £500 in marked notes in an undercover operation to snare suspected drug dealers, a court heard.

Two officers, known only as Jay and Geordie, bought the class A drug from a man in a pre-arranged deal in a railway station car park, a jury at Lewes Crown Court was told yesterday.

Speaking from behind special screens to conceal their identities, the detectives said they arranged the deal with a man known only as X in a call to his mobile phone.

A rendezvous was set for Preston Park railway station at 2.25pm on November 6 last year.

The detectives told the court a Vauxhall Nova pulled into the car park with two white females in the front and two black males in the back.

One of the men left the car and got into the back of the officers' car.

A deal was made and one of the officers handed over £500 in marked £10 and £20 notes in exchange for crack cocaine.

The jury was told the dealer then agreed to go for a drink with the detectives and the trio drove off to a car park on Preston Road, Brighton, followed by the Nova.

During the journey, X talked about further drug deals and said he was also known by the nick-name Words, it was alleged.

Later the same day, police swooped on the car while it was parked in the Caffyns Audi garage in Dyke Road, Brighton.

The driver Amy Scott, 20, of Princess Crescent, Brighton, and Adam Brooks, 21, of Zion Gardens, Brighton, were arrested with the other two occupants.

The court heard Scott was found with £30 of police marked notes in her possession. Brooks allegedly had £370 in his hands and trouser pocket. There was also £100 in cash where he had been sitting in the car.

Detective Sergeant Tony Pike, who took part in the swoop, said: "Mr Brooks was handcuffed and brought out of the vehicle.

"He was wearing jogging bottoms which were falling down, exposing his underpants.

"I was attempting to pull them up.

"I held on to the left hand side of them and felt a flat item in his pocket. It was a wad of folded paper money."

Mr Pike told the court Brooks became agitated and was protesting his innocence.

At this point one of the uniformed officers sprayed Brooks with pepper spray because he believed Brooks had drugs in his mouth.

No drugs were recovered during the swoop.

Scott and Brooks have both pleaded not guilty to supplying crack cocaine.

The trial continues.